Introduce the MTState

The HWState keeps, for good reason, both touching fingers and fingers
going away. However, this implies that additional logic is needed to
keep track of the number of actual touching fingers. In particular
the test for touching fingers is somewhat misplaced in hwstate.c.
Moreover, HWState should only exist in one instance, since it contains
data which does not need to be referred to during gesture extraction.

This patch introduces the MTState structure, which keeps more digested
data for gesture extraction. In particular, it only keeps the actual
touches.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

1 files changed, 93 insertions, 0 deletions

diff --git a/src/mtstate.c b/src/mtstate.c
new file mode 100644
index 0000000..a8541dc
--- /dev/null
+++ b/src/mtstate.c
@@ -0,0 +1,93 @@
+/***************************************************************************
+ *
+ * Multitouch X driver
+ * Copyright (C) 2008 Henrik Rydberg <rydberg@euromail.se>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ **************************************************************************/
+
+#include "mtstate.h"
+
+#define TOUCH_WIDTH(hw) (0.05 * hw->width_major)
+#define TOUCH_SCALE(caps) (0.05 * caps->abs_touch_major.maximum)
+
+void init_mtstate(struct MTState *s)
+{
+	memset(s, 0, sizeof(struct MTState));
+}
+
+static int touching_finger(const struct FingerData *hw,
+			   const struct Capabilities *caps)
+{
+	if (caps->has_touch_major && caps->has_width_major)
+		return hw->touch_major > TOUCH_WIDTH(hw);
+	if (caps->has_touch_major)
+		return hw->touch_major > TOUCH_SCALE(caps);
+	return 1;
+}
+
+void extract_mtstate(struct MTState *s,
+		     const struct HWState *hs,
+		     const struct Capabilities *caps)
+{
+	int i;
+
+	s->nfinger = 0;
+	for (i = 0; i < hs->nfinger; i++)
+		if (touching_finger(&hs->finger[i].hw, caps))
+			s->finger[s->nfinger++] = hs->finger[i];
+
+	s->button = hs->button;
+	s->evtime = hs->evtime;
+}
+
+const struct FingerState *find_finger(const struct MTState *s, int id)
+{
+	int i;
+
+	for (i = 0; i < s->nfinger; i++)
+		if (s->finger[i].id == id)
+			return s->finger + i;
+
+	return NULL;
+}
+
+void output_mtstate(const struct MTState *s)
+{
+	int i;
+	xf86Msg(X_INFO, "buttons: %d%d%d\n",
+		GETBIT(s->button, MT_BUTTON_LEFT),
+		GETBIT(s->button, MT_BUTTON_MIDDLE),
+		GETBIT(s->button, MT_BUTTON_RIGHT));
+	xf86Msg(X_INFO, "fingers: %d\n",
+		s->nfinger);
+	xf86Msg(X_INFO, "evtime: %lld\n",
+		s->evtime);
+	for (i = 0; i < s->nfinger; i++) {
+		xf86Msg(X_INFO,
+			"  %+02d %+05d:%+05d +%05d:%+05d "
+			"%+06d %+06d %+05d:%+05d\n",
+			s->finger[i].id,
+			s->finger[i].hw.touch_major,
+			s->finger[i].hw.touch_minor,
+			s->finger[i].hw.width_major,
+			s->finger[i].hw.width_minor,
+			s->finger[i].hw.orientation,
+			s->finger[i].hw.pressure,
+			s->finger[i].hw.position_x,
+			s->finger[i].hw.position_y);
+	}
+}